Exchanging location information of a base station that is associated with a plurality of different transmission point locations

ABSTRACT

In an embodiment, a network entity (e.g., a base station, a location server, etc.) transmits, to a user equipment (UE), at least one base station almanac (BSA) message that indicates (i) a set of transmission point locations associated with at least one base station, the set of transmission point locations including at least one transmission point location of a base station that is based upon a plurality of different transmission point locations associated with the base station, and (ii) a mapping of each of a plurality of beams to the at least one transmission point location. The UE receives the transmitted at least one BSA message.

CROSS-REFERENCE TO RELATED APPLICATION

The present application for patent claims priority under 35 U.S.C. § 119to Greek Patent Application No. 20180100242 entitled, “EXCHANGINGLOCATION INFORMATION OF A BASE STATION THAT IS ASSOCIATED WITH APLURALITY OF DIFFERENT TRANSMISSION POINT LOCATIONS”, filed with theGreek Patent and Trademark Office on Jun. 5, 2018, and assigned to theassignee hereof and hereby expressly incorporated herein by reference inits entirety.

TECHNICAL FIELD

Various aspects described herein generally relate to wirelesscommunication systems, and more particularly, to exchanging locationinformation of a base station that is associated with a plurality ofdifferent transmission point locations.

BACKGROUND

Wireless communication systems have developed through variousgenerations, including a first-generation analog wireless phone service(1G), a second-generation (2G) digital wireless phone service (includinginterim 2.5G and 2.75G networks), a third-generation (3G) high speeddata, Internet-capable wireless service and a fourth-generation (4G)service (e.g., Long Term Evolution (LTE) or WiMax). There are presentlymany different types of wireless communication systems in use, includingCellular and Personal Communications Service (PCS) systems. Examples ofknown cellular systems include the cellular Analog Advanced Mobile PhoneSystem (AMPS), and digital cellular systems based on Code DivisionMultiple Access (CDMA), Frequency Division Multiple Access (FDMA), TimeDivision Multiple Access (TDMA), the Global System for Mobile access(GSM) variation of TDMA, etc.

A fifth generation (5G) mobile standard calls for higher data transferspeeds, greater numbers of connections, and better coverage, among otherimprovements. The 5G standard, according to the Next Generation MobileNetworks Alliance, is designed to provide data rates of several tens ofmegabits per second to each of tens of thousands of users, with 1gigabit per second to tens of workers on an office floor. Severalhundreds of thousands of simultaneous connections should be supported inorder to support large sensor deployments. Consequently, the spectralefficiency of 5G mobile communications should be significantly enhancedcompared to the current 4G standard. Furthermore, signaling efficienciesshould be enhanced and latency should be substantially reduced comparedto current standards.

Some wireless communication networks, such as 5G, support operation atvery high and even extremely-high frequency (EHF) bands, such asmillimeter wave (mmW) frequency bands (generally, wavelengths of 1 mm to10 mm, or 30 to 300 GHz). These extremely high frequencies may supportvery high throughput such as up to six gigabits per second (Gbps). Oneof the challenges for wireless communication at very high or extremelyhigh frequencies, however, is that a significant propagation loss mayoccur due to the high frequency. As the frequency increases, thewavelength may decrease, and the propagation loss may increase as well.At mmW frequency bands, the propagation loss may be severe. For example,the propagation loss may be on the order of 22 to 27 dB, relative tothat observed in either the 2.4 GHz, or 5 GHz bands.

Propagation loss is also an issue in Multiple Input-Multiple Output(MIMO) and massive MIMO systems in any band. The term MIMO as usedherein will generally refer to both MIMO and massive MIMO. MIMO is amethod for multiplying the capacity of a radio link by using multipletransmit and receive antennas to exploit multipath propagation.Multipath propagation occurs because radio frequency (RF) signals notonly travel by the shortest path between the transmitter and receiver,which may be a line of sight (LOS) path, but also over a number of otherpaths as they spread out from the transmitter and reflect off otherobjects such as hills, buildings, water, and the like on their way tothe receiver. A transmitter in a MIMO system includes multiple antennasand takes advantage of multipath propagation by directing these antennasto each transmit the same RF signals on the same radio channel to areceiver. The receiver is also equipped with multiple antennas tuned tothe radio channel that can detect the RF signals sent by thetransmitter. As the RF signals arrive at the receiver (some RF signalsmay be delayed due to the multipath propagation), the receiver cancombine them into a single RF signal. Because the transmitter sends eachRF signal at a lower power level than it would send a single RF signal,propagation loss is also an issue in a MIMO system.

To address propagation loss issues in mmW band systems and MIMO systems,transmitters may use beamforming to extend RF signal coverage. Inparticular, transmit beamforming is a technique for emitting an RFsignal in a specific direction, whereas receive beamforming is atechnique used to increase receive sensitivity of RF signals that arriveat a receiver along a specific direction. Transmit beamforming andreceive beamforming may be used in conjunction with each other orseparately, and references to “beamforming” may hereinafter refer totransmit beamforming, receive beamforming, or both. Traditionally, whena transmitter broadcasts an RF signal, it broadcasts the RF signal innearly all directions determined by the fixed antenna pattern orradiation pattern of the antenna. With beamforming, the transmitterdetermines where a given receiver is located relative to the transmitterand projects a stronger downlink RF signal in that specific direction,thereby providing a faster (in terms of data rate) and stronger RFsignal for the receiver. To change the directionality of the RF signalwhen transmitting, a transmitter can control the phase and relativeamplitude of the RF signal broadcasted by each antenna. For example, atransmitter may use an array of antennas (also referred to as a “phasedarray” or an “antenna array”) that creates a beam of RF waves that canbe “steered” to point in different directions, without actually movingthe antennas. Specifically, the RF current is fed to the individualantennas with the correct phase relationship so that the radio wavesfrom the separate antennas add together to increase the radiation in adesired direction, while cancelling the radio waves from the separateantennas to suppress radiation in undesired directions.

To support position estimations in terrestrial wireless networks, amobile device can be configured to measure and report the observed timedifference of arrival (OTDOA) or reference signal timing difference(RSTD) between reference RF signals received from two or more networknodes (e.g., different base stations or different transmission points(e.g., antennas) belonging to the same base station).

Where a transmitter uses beamforming to transmit RF signals, the beamsof interest for data communication between the transmitter and receiverwill be the beams carrying RF signals having the highest received signalstrength (or highest received Signal to Noise plus Interference Ratio(SINR), for example, in the presence of a directional interferingsignal). However, the receiver's ability to perform certain tasks maysuffer when the receiver relies upon the beam with the highest receivedsignal strength. For example, in a scenario where the beam with thehighest received signal strength travels over a non-LOS (NLOS) path thatis longer than the shortest path (i.e., a LOS path or a shortest NLOSpath), the RF signals may arrive later than RF signal(s) received overthe shortest path due to propagation delay. Accordingly, if the receiveris performing a task that requires precise timing measurements, and thebeam with the highest received signal strength is affected by longerpropagation delay, then the beam with the highest received signalstrength may not be optimal for the task at hand.

SUMMARY

An embodiment is directed to a method of operating a user equipment(UE), comprising receiving, from a network entity, at least one basestation almanac (BSA) message that indicates (i) a set of transmissionpoint locations associated with at least one base station, the set oftransmission point locations including at least one transmission pointlocation of a base station that is based upon a plurality of differenttransmission point locations associated with the base station, and (ii)a mapping of each of a plurality of beams to the at least onetransmission point location.

Another embodiment is directed to a method of operating a networkentity, comprising transmitting, to a user equipment (UE), at least onebase station almanac (BSA) message that indicates (i) a set oftransmission point locations associated with at least one base station,the set of transmission point locations including at least onetransmission point location of a base station that is based upon aplurality of different transmission point locations associated with thebase station, and (ii) a mapping of each of a plurality of beams to theat least one transmission point location.

Another embodiment is directed to a user equipment (UE), comprising amemory, and means for receiving, from a network entity, at least onebase station almanac (BSA) message that indicates (i) a set oftransmission point locations associated with at least one base station,the set of transmission point locations including at least onetransmission point location of a base station that is based upon aplurality of different transmission point locations associated with thebase station, and (ii) a mapping of each of a plurality of beams to theat least one transmission point location.

Another embodiment is directed to a network entity, comprising a memory,and means for transmitting, to a user equipment (UE), at least one basestation almanac (BSA) message that indicates (i) a set of transmissionpoint locations associated with the at least one base station, the setof transmission point locations including at least one transmissionpoint location of a base station that is based upon a plurality ofdifferent transmission point locations associated with the base station,and (ii) a mapping of each of a plurality of beams to the at least onetransmission point location.

Another embodiment is directed to a user equipment (UE), comprising amemory, at least one transceiver, and at least one processor coupled tothe memory and the at least one transceiver and configured to receive,from a network entity, at least one base station almanac (BSA) messagethat indicates (i) a set of transmission point locations associated withat least one base station, the set of transmission point locationsincluding at least one transmission point location of a base stationthat is based upon a plurality of different transmission point locationsassociated with the base station, and (ii) a mapping of each of aplurality of beams to the at least one transmission point location.

Another embodiment is directed to a network entity, comprising a memory,at least one communication interface, and at least one processor coupledto the memory and the at least one communication interface andconfigured to transmit, to a user equipment (UE), at least one basestation almanac (BSA) message that indicates (i) a set of transmissionpoint locations associated with at least one base station, the set oftransmission point locations including at least one transmission pointlocation of a base station that is based upon a plurality of differenttransmission point locations associated with the base station, and (ii)a mapping of each of a plurality of beams to the at least onetransmission point location.

Another embodiment is directed to a non-transitory computer-readablemedium containing instructions stored thereon, which, when executed by auser equipment (UE), cause the UE to perform operations, theinstructions comprising at least one instruction to cause the UE toreceive, from a network entity, at least one base station almanac (BSA)message that indicates (i) a set of transmission point locationsassociated with at least one base station, the set of transmission pointlocations including at least one transmission point location of a basestation that is based upon a plurality of different transmission pointlocations associated with the base station, and (ii) a mapping of eachof a plurality of beams to the at least one transmission point location.

Another embodiment is directed to a non-transitory computer-readablemedium containing instructions stored thereon, which, when executed by anetwork entity, cause the network entity to perform operations, theinstructions comprising at least one instruction to cause the networkentity to transmit, to a user equipment (UE), at least one base stationalmanac (BSA) message that indicates (i) a set of transmission pointlocations associated with at least one base station, the set oftransmission point locations including at least one transmission pointlocation of a base station that is based upon a plurality of differenttransmission point locations associated with the base station, and (ii)a mapping of each of a plurality of beams to the at least onetransmission point location.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the various aspects described herein andmany attendant advantages thereof will be readily obtained as the samebecomes better understood by reference to the following detaileddescription when considered in connection with the accompanying drawingswhich are presented solely for illustration and not limitation, and inwhich:

FIG. 1 illustrates an exemplary wireless communications system,according to various aspects.

FIGS. 2A and 2B illustrate example wireless network structures,according to various aspects.

FIG. 3A illustrates an exemplary base station and an exemplary UE in anaccess network, according to various aspects.

FIG. 3B illustrates an exemplary server according to various aspects ofthe disclosure.

FIG. 4 illustrates an exemplary wireless communications system accordingto various aspects of the disclosure.

FIG. 5 illustrates an exemplary wireless communications system accordingto various aspects of the disclosure.

FIG. 6A is a graph showing the RF channel response at a UE over timeaccording to aspects of the disclosure.

FIG. 6B illustrates an exemplary separation of clusters in Angle ofDeparture (AoD) according to aspects of the disclosure.

FIGS. 7-8 and 10-12 illustrate exemplary methods, according to variousaspects.

FIG. 9 illustrates an arrangement of beams being transmitted by a basestation in accordance with an embodiment of the disclosure.

DETAILED DESCRIPTION

Various aspects described herein generally relate to exchanging locationinformation of a base station that is associated with a plurality ofdifferent transmission point locations. In an embodiment, a userequipment (UE) receives, from a network entity (e.g., a base station, aserver, etc.), at least one base station almanac (BSA) message thatindicates (i) a set of transmission point locations associated with atleast one base station, the set of transmission point locationsincluding at least one transmission point location of a base stationthat is based upon a plurality of different transmission point locationsassociated with the base station, and (ii) a mapping of each of aplurality of beams to the at least one transmission point location. TheUE receives, from the base station, the plurality of beams in accordancewith the mapping. The UE then estimates a position of the UE based atleast in part upon (i) one or more measurements performed by the UE onone or more of the plurality of beams and (ii) the at least onetransmission point location to which the one or more beams are mapped.

These and other aspects are disclosed in the following description andrelated drawings to show specific examples relating to exemplaryaspects. Alternate aspects will be apparent to those skilled in thepertinent art upon reading this disclosure, and may be constructed andpracticed without departing from the scope or spirit of the disclosure.Additionally, well-known elements will not be described in detail or maybe omitted so as to not obscure the relevant details of the aspectsdisclosed herein.

The word “exemplary” is used herein to mean “serving as an example,instance, or illustration.” Any aspect described herein as “exemplary”is not necessarily to be construed as preferred or advantageous overother aspects. Likewise, the term “aspects” does not require that allaspects include the discussed feature, advantage, or mode of operation.

The terminology used herein describes particular aspects only and shouldnot be construed to limit any aspects disclosed herein. As used herein,the singular forms “a,” “an,” and “the” are intended to include theplural forms as well, unless the context clearly indicates otherwise.Those skilled in the art will further understand that the terms“comprises,” “comprising,” “includes,” and/or “including,” as usedherein, specify the presence of stated features, integers, steps,operations, elements, and/or components, but do not preclude thepresence or addition of one or more other features, integers, steps,operations, elements, components, and/or groups thereof.

Further, various aspects may be described in terms of sequences ofactions to be performed by, for example, elements of a computing device.Those skilled in the art will recognize that various actions describedherein can be performed by specific circuits (e.g., an applicationspecific integrated circuit (ASIC)), by program instructions beingexecuted by one or more processors, or by a combination of both.Additionally, these sequences of actions described herein can beconsidered to be embodied entirely within any form of non-transitorycomputer-readable medium having stored thereon a corresponding set ofcomputer instructions that upon execution would cause an associatedprocessor to perform the functionality described herein. Thus, thevarious aspects described herein may be embodied in a number ofdifferent forms, all of which have been contemplated to be within thescope of the claimed subject matter. In addition, for each of theaspects described herein, the corresponding form of any such aspects maybe described herein as, for example, “logic configured to” and/or otherstructural components configured to perform the described action.

As used herein, the terms “user equipment” (or “UE”), “user device,”“user terminal,” “client device,” “communication device,” “wirelessdevice,” “wireless communications device,” “handheld device,” “mobiledevice,” “mobile terminal,” “mobile station,” “handset,” “accessterminal,” “subscriber device,” “subscriber terminal,” “subscriberstation,” “terminal,” and variants thereof may interchangeably refer toany suitable mobile or stationary device that can receive wirelesscommunication and/or navigation signals. These terms are also intendedto include devices which communicate with another device that canreceive wireless communication and/or navigation signals such as byshort-range wireless, infrared, wireline connection, or otherconnection, regardless of whether satellite signal reception, assistancedata reception, and/or position-related processing occurs at the deviceor at the other device. In addition, these terms are intended to includeall devices, including wireless and wireline communication devices, thatcan communicate with a core network via a radio access network (RAN),and through the core network the UEs can be connected with externalnetworks such as the Internet and with other UEs. Of course, othermechanisms of connecting to the core network and/or the Internet arealso possible for the UEs, such as over a wired access network, awireless local area network (WLAN) (e.g., based on IEEE 802.11, etc.)and so on. UEs can be embodied by any of a number of types of devicesincluding but not limited to printed circuit (PC) cards, compact flashdevices, external or internal modems, wireless or wireline phones,smartphones, tablets, tracking devices, asset tags, and so on. Acommunication link through which UEs can send signals to a RAN is calledan uplink channel (e.g., a reverse traffic channel, a reverse controlchannel, an access channel, etc.). A communication link through whichthe RAN can send signals to UEs is called a downlink or forward linkchannel (e.g., a paging channel, a control channel, a broadcast channel,a forward traffic channel, etc.). As used herein the term trafficchannel (TCH) can refer to either an uplink/reverse or downlink/forwardtraffic channel.

According to various aspects, FIG. 1 illustrates an exemplary wirelesscommunications system 100. The wireless communications system 100 (whichmay also be referred to as a wireless wide area network (WWAN)) mayinclude various base stations 102 and various UEs 104. The base stations102 may include macro cells (high power cellular base stations) and/orsmall cells (low power cellular base stations), wherein the macro cellsmay include Evolved NodeBs (eNBs), where the wireless communicationssystem 100 corresponds to an LTE network, or gNodeBs (gNBs), where thewireless communications system 100 corresponds to a 5G network or acombination of both, and the small cells may include femtocells,picocells, microcells, etc.

The base stations 102 may collectively form a Radio Access Network (RAN)and interface with an Evolved Packet Core (EPC) or Next Generation Core(NGC) through backhaul links. In addition to other functions, the basestations 102 may perform functions that relate to one or more oftransferring user data, radio channel ciphering and deciphering,integrity protection, header compression, mobility control functions(e.g., handover, dual connectivity), inter-cell interferencecoordination, connection setup and release, load balancing, distributionfor non-access stratum (NAS) messages, NAS node selection,synchronization, RAN sharing, multimedia broadcast multicast service(MBMS), subscriber and equipment trace, RAN information management(RIM), paging, positioning, and delivery of warning messages. The basestations 102 may communicate with each other directly or indirectly(e.g., through the EPC/NGC) over backhaul links 134, which may be wiredor wireless.

The base stations 102 may wirelessly communicate with the UEs 104. Eachof the base stations 102 may provide communication coverage for arespective geographic coverage area 110. In an aspect, although notshown in FIG. 1, geographic coverage areas 110 may be subdivided into aplurality of cells (e.g., three), or sectors, each cell corresponding toa single antenna or array of antennas of a base station 102. As usedherein, the term “cell” or “sector” may correspond to one of a pluralityof cells of a base station 102, or to the base station 102 itself,depending on the context.

While neighboring macro cell geographic coverage areas 110 may partiallyoverlap (e.g., in a handover region), some of the geographic coverageareas 110 may be substantially overlapped by a larger geographiccoverage area 110. For example, a small cell base station 102′ may havea geographic coverage area 110′ that substantially overlaps with thegeographic coverage area 110 of one or more macro cell base stations102. A network that includes both small cell and macro cells may beknown as a heterogeneous network. A heterogeneous network may alsoinclude Home eNBs (HeNBs), which may provide service to a restrictedgroup known as a closed subscriber group (CSG). The communication links120 between the base stations 102 and the UEs 104 may include uplink(UL) (also referred to as reverse link) transmissions from a UE 104 to abase station 102 and/or downlink (DL) (also referred to as forward link)transmissions from a base station 102 to a UE 104. The communicationlinks 120 may use MIMO antenna technology, including spatialmultiplexing, beamforming, and/or transmit diversity. The communicationlinks 120 may be through one or more carriers. Allocation of carriersmay be asymmetric with respect to DL and UL (e.g., more or less carriersmay be allocated for DL than for UL).

The wireless communications system 100 may further include a wirelesslocal area network (WLAN) access point (AP) 150 in communication withWLAN stations (STAs) 152 via communication links 154 in an unlicensedfrequency spectrum (e.g., 5 GHz). When communicating in an unlicensedfrequency spectrum, the WLAN STAs 152 and/or the WLAN AP 150 may performa clear channel assessment (CCA) prior to communicating in order todetermine whether the channel is available.

The small cell base station 102′ may operate in a licensed and/or anunlicensed frequency spectrum. When operating in an unlicensed frequencyspectrum, the small cell base station 102′ may employ LTE or 5Gtechnology and use the same 5 GHz unlicensed frequency spectrum as usedby the WLAN AP 150. The small cell base station 102′, employing LTE/5Gin an unlicensed frequency spectrum, may boost coverage to and/orincrease capacity of the access network. LTE in an unlicensed spectrummay be referred to as LTE-unlicensed (LTE-U), licensed assisted access(LAA), or MulteFire.

The wireless communications system 100 may further include a mmW basestation 180 that may operate in mmW frequencies and/or near mmWfrequencies in communication with a UE 182. Extremely high frequency(EHF) is part of the RF in the electromagnetic spectrum. EHF has a rangeof 30 GHz to 300 GHz and a wavelength between 1 millimeter and 10millimeters. Radio waves in this band may be referred to as a millimeterwave. Near mmW may extend down to a frequency of 3 GHz with a wavelengthof 100 millimeters. The super high frequency (SHF) band extends between3 GHz and 30 GHz, also referred to as centimeter wave. Communicationsusing the mmW/near mmW radio frequency band have high path loss and arelatively short range. The mmW base station 180 may utilize beamforming184 with the UE 182 to compensate for the extremely high path loss andshort range. Further, it will be appreciated that in alternativeconfigurations, one or more base stations 102 may also transmit usingmmW or near mmW and beamforming 184. Accordingly, it will be appreciatedthat the foregoing illustrations are merely examples and should not beconstrued to limit the various aspects disclosed herein.

The wireless communications system 100 may further include one or moreUEs, such as UE 190, that connects indirectly to one or morecommunication networks via one or more device-to-device (D2D)peer-to-peer (P2P) links. In the embodiment of FIG. 1, UE 190 has a D2DP2P link 192 with one of the UEs 104 connected to one of the basestations 102 (e.g., through which UE 190 may indirectly obtain cellularconnectivity) and a D2D P2P link 194 with WLAN STA 152 connected to theWLAN AP 150 (through which UE 190 may indirectly obtain WLAN-basedInternet connectivity). In an example, the D2D P2P links 192-194 may besupported with any well-known D2D radio access technology (RAT), such asLTE Direct (LTE-D), WiFi Direct (WiFi-D), Bluetooth, and so on.

According to various aspects, FIG. 2A illustrates an example wirelessnetwork structure 200. For example, a Next Generation Core (NGC) 210 canbe viewed functionally as control plane functions 214 (e.g., UEregistration, authentication, network access, gateway selection, etc.)and user plane functions 212, (e.g., UE gateway function, access to datanetworks, IP routing, etc.) which operate cooperatively to form the corenetwork. User plane interface (NG-U) 213 and control plane interface(NG-C) 215 connect the gNB 222 to the NGC 210 and specifically to thecontrol plane functions 214 and user plane functions 212. In anadditional configuration, an eNB 224 may also be connected to the NGC210 via NG-C 215 to the control plane functions 214 and NG-U 213 to userplane functions 212. Further, eNB 224 may directly communicate with gNB222 via a backhaul connection 223. Accordingly, in some configurations,the New RAN 220 may only have one or more gNBs 222, while otherconfigurations include one or more of both eNBs 224 and gNBs 222. EithergNB 222 or eNB 224 may communicate with UEs 240 (e.g., any of the UEsdepicted in FIG. 1, such as UEs 104, UE 182, UE 190, etc.). Anotheroptional aspect may include Location Server 230 which may be incommunication with the NGC 210 to provide location assistance for UEs240. The location server 230 can be implemented as a plurality ofstructurally separate servers, or alternately may each correspond to asingle server. The location server 230 can be configured to support oneor more location services for UEs 240 that can connect to the locationserver 230 via the core network, NGC 210, and/or via the Internet (notillustrated). Further, the location server 230 may be integrated into acomponent of the core network, or alternatively may be external to thecore network.

According to various aspects, FIG. 2B illustrates another examplewireless network structure 250. For example, Evolved Packet Core (EPC)260 can be viewed functionally as control plane functions, MobilityManagement Entity (MME) 264 and user plane functions, Packet DataNetwork Gateway/Serving Gateway (P/SGW) 262, which operate cooperativelyto form the core network. S1 user plane interface (S1-U) 263 and S1control plane interface (S1-MME) 265 connect the eNB 224 to the EPC 260and specifically to MME 264 and P/SGW 262. In an additionalconfiguration, a gNB 222 may also be connected to the EPC 260 via S1-MME265 to MME 264 and S1-U 263 to P/SGW 262. Further, eNB 224 may directlycommunicate to gNB 222 via the backhaul connection 223, with or withoutgNB 222 direct connectivity to the EPC 260. Accordingly, in someconfigurations, the New RAN 220 may only have one or more gNBs 222,while other configurations include one or more of both eNBs 224 and gNBs222. Either gNB 222 or eNB 224 may communicate with UEs 240 (e.g., anyof the UEs depicted in FIG. 1, such as UEs 104, UE 182, UE 190, etc.).Another optional aspect may include Location Server 230 which may be incommunication with the EPC 260 to provide location assistance for UEs240. The location server 230 can be implemented as a plurality ofstructurally separate servers, or alternately may each correspond to asingle server. The location server 230 can be configured to support oneor more location services for UEs 240 that can connect to the locationserver 230 via the core network, EPC 260, and/or via the Internet (notillustrated).

According to various aspects, FIG. 3A illustrates an exemplary basestation 310 (e.g., an eNB, a gNB, a small cell AP, a WLAN AP, etc.) incommunication with an exemplary UE 350 in a wireless network. In the DL,IP packets from the core network (NGC 210/EPC 260) may be provided to acontroller/processor 375. The controller/processor 375 implementsfunctionality for a radio resource control (RRC) layer, a packet dataconvergence protocol (PDCP) layer, a radio link control (RLC) layer, anda medium access control (MAC) layer. The controller/processor 375provides RRC layer functionality associated with broadcasting of systeminformation (e.g., MIB, SIBs), RRC connection control (e.g., RRCconnection paging, RRC connection establishment, RRC connectionmodification, and RRC connection release), inter-RAT mobility, andmeasurement configuration for UE measurement reporting; PDCP layerfunctionality associated with header compression/decompression, security(ciphering, deciphering, integrity protection, integrity verification),and handover support functions; RLC layer functionality associated withthe transfer of upper layer packet data units (PDUs), error correctionthrough ARQ, concatenation, segmentation, and reassembly of RLC servicedata units (SDUs), re-segmentation of RLC data PDUs, and reordering ofRLC data PDUs; and MAC layer functionality associated with mappingbetween logical channels and transport channels, scheduling informationreporting, error correction, priority handling, and logical channelprioritization.

The transmit (TX) processor 316 and the receive (RX) processor 370implement Layer-1 functionality associated with various signalprocessing functions. Layer-1, which includes a physical (PHY) layer,may include error detection on the transport channels, forward errorcorrection (FEC) coding/decoding of the transport channels,interleaving, rate matching, mapping onto physical channels,modulation/demodulation of physical channels, and MIMO antennaprocessing. The TX processor 316 handles mapping to signalconstellations based on various modulation schemes (e.g., binaryphase-shift keying (BPSK), quadrature phase-shift keying (QPSK),M-phase-shift keying (M-PSK), M-quadrature amplitude modulation(M-QAM)). The coded and modulated symbols may then be split intoparallel streams. Each stream may then be mapped to an OFDM subcarrier,multiplexed with a reference signal (e.g., pilot) in the time and/orfrequency domain, and then combined together using an Inverse FastFourier Transform (IFFT) to produce a physical channel carrying a timedomain OFDM symbol stream. The OFDM stream is spatially precoded toproduce multiple spatial streams. Channel estimates from a channelestimator 374 may be used to determine the coding and modulation scheme,as well as for spatial processing. The channel estimate may be derivedfrom a reference signal and/or channel condition feedback transmitted bythe UE 350. Each spatial stream may then be provided to one or moredifferent antennas 320 via a separate transmitter 318TX. Eachtransmitter 318TX may modulate an RF carrier with a respective spatialstream for transmission.

At the UE 350, each receiver 354RX receives a signal through itsrespective antenna 352. Each receiver 354RX recovers informationmodulated onto an RF carrier and provides the information to the RXprocessor 356. The TX processor 368 and the RX processor 356 implementLayer-1 functionality associated with various signal processingfunctions. The RX processor 356 may perform spatial processing on theinformation to recover any spatial streams destined for the UE 350. Ifmultiple spatial streams are destined for the UE 350, they may becombined by the RX processor 356 into a single OFDM symbol stream. TheRX processor 356 then converts the OFDM symbol stream from thetime-domain to the frequency domain using a Fast Fourier Transform(FFT). The frequency domain signal comprises a separate OFDM symbolstream for each subcarrier of the OFDM signal. The symbols on eachsubcarrier, and the reference signal, are recovered and demodulated bydetermining the most likely signal constellation points transmitted bythe base station 310. These soft decisions may be based on channelestimates computed by the channel estimator 358. The soft decisions arethen decoded and de-interleaved to recover the data and control signalsthat were originally transmitted by the base station 310 on the physicalchannel. The data and control signals are then provided to thecontroller/processor 359, which implements Layer-3 and Layer-2functionality.

The controller/processor 359 can be associated with a memory 360 thatstores program codes and data. The memory 360 may be referred to as acomputer-readable medium. In the UL, the controller/processor 359provides demultiplexing between transport and logical channels, packetreassembly, deciphering, header decompression, and control signalprocessing to recover IP packets from the core network. Thecontroller/processor 359 is also responsible for error detection.

Similar to the functionality described in connection with the DLtransmission by the base station 310, the controller/processor 359provides RRC layer functionality associated with system information(e.g., MIB, SIBs) acquisition, RRC connections, and measurementreporting; PDCP layer functionality associated with headercompression/decompression, and security (ciphering, deciphering,integrity protection, integrity verification); RLC layer functionalityassociated with the transfer of upper layer PDUs, error correctionthrough ARQ, concatenation, segmentation, and reassembly of RLC SDUs,re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; andMAC layer functionality associated with mapping between logical channelsand transport channels, multiplexing of MAC SDUs onto TBs,demultiplexing of MAC SDUs from TBs, scheduling information reporting,error correction through HARQ, priority handling, and logical channelprioritization.

Channel estimates derived by the channel estimator 358 from a referencesignal or feedback transmitted by the base station 310 may be used bythe TX processor 368 to select the appropriate coding and modulationschemes, and to facilitate spatial processing. The spatial streamsgenerated by the TX processor 368 may be provided to different antenna352 via separate transmitters 354TX. Each transmitter 354TX may modulatean RF carrier with a respective spatial stream for transmission.

The UL transmission is processed at the base station 310 in a mannersimilar to that described in connection with the receiver function atthe UE 350. Each receiver 318RX receives a signal through its respectiveantenna 320. Each receiver 318RX recovers information modulated onto anRF carrier and provides the information to a RX processor 370.

The controller/processor 375 can be associated with a memory 376 thatstores program codes and data. The memory 376 may be referred to as acomputer-readable medium. In the UL, the controller/processor 375provides demultiplexing between transport and logical channels, packetreassembly, deciphering, header decompression, control signal processingto recover IP packets from the UE 350. IP packets from thecontroller/processor 375 may be provided to the core network. Thecontroller/processor 375 is also responsible for error detection.

FIG. 3B illustrates an exemplary server 300B. In an example, the server300B may correspond to one example configuration of the location server230 described above. In FIG. 3B, the server 300B includes a processor301B coupled to volatile memory 302B and a large capacity nonvolatilememory, such as a disk drive 303B. The server 300B may also include afloppy disc drive, compact disc (CD) or DVD disc drive 306B coupled tothe processor 301B. The server 300B may also include network accessports 304B coupled to the processor 301B for establishing dataconnections with a network 307B, such as a local area network coupled toother broadcast system computers and servers or to the Internet.

FIG. 4 illustrates an exemplary wireless communications system 400according to various aspects of the disclosure. In the example of FIG.4, a UE 404, which may correspond to any of the UEs described above withrespect to FIG. 1 (e.g., UEs 104, UE 182, UE 190, etc.), is attemptingto calculate an estimate of its position, or assist another entity(e.g., a base station or core network component, another UE, a locationserver, a third party application, etc.) to calculate an estimate of itsposition. The UE 404 may communicate wirelessly with a plurality of basestations 402 a-d (collectively, base stations 402), which may correspondto any combination of base stations 102 or 180 and/or WLAN AP 150 inFIG. 1, using RF signals and standardized protocols for the modulationof the RF signals and the exchange of information packets. By extractingdifferent types of information from the exchanged RF signals, andutilizing the layout of the wireless communications system 400 (i.e.,the base stations locations, geometry, etc.), the UE 404 may determineits position, or assist in the determination of its position, in apredefined reference coordinate system. In an aspect, the UE 404 mayspecify its position using a two-dimensional coordinate system; however,the aspects disclosed herein are not so limited, and may also beapplicable to determining positions using a three-dimensional coordinatesystem, if the extra dimension is desired. Additionally, while FIG. 4illustrates one UE 404 and four base stations 402, as will beappreciated, there may be more UEs 404 and more or fewer base stations402.

To support position estimates, the base stations 402 may be configuredto broadcast reference RF signals (e.g., Positioning Reference Signals(PRS), Cell-specific Reference Signals (CRS), Channel State InformationReference Signals (CSI-RS), synchronization signals, etc.) to UEs 404 intheir coverage areas to enable a UE 404 to measure reference RF signaltiming differences (e.g., OTDOA or RSTD) between pairs of network nodesand/or to identify the beam that best excite the LOS or shortest radiopath between the UE 404 and the transmitting base stations 402.Identifying the LOS/shortest path beam(s) is of interest not onlybecause these beams can subsequently be used for OTDOA measurementsbetween a pair of base stations 402, but also because identifying thesebeams can directly provide some positioning information based on thebeam direction. Moreover, these beams can subsequently be used for otherposition estimation methods that require precise ToA, such as round-triptime estimation based methods.

As used herein, a “network node” may be a base station 402, a cell of abase station 402, a remote radio head, an antenna of a base station 402,where the locations of the antennas of a base station 402 are distinctfrom the location of the base station 402 itself, or any other networkentity capable of transmitting reference signals. Further, as usedherein, a “node” may refer to either a network node or a UE.

A location server (e.g., location server 230) may send assistance datato the UE 404 that includes an identification of one or more neighborcells of base stations 402 and configuration information for referenceRF signals transmitted by each neighbor cell. Alternatively, theassistance data can originate directly from the base stations 402themselves (e.g., in periodically broadcasted overhead messages, etc.).Alternatively, the UE 404 can detect neighbor cells of base stations 402itself without the use of assistance data. The UE 404 (e.g., based inpart on the assistance data, if provided) can measure and (optionally)report the OTDOA from individual network nodes and/or RSTDs betweenreference RF signals received from pairs of network nodes. Using thesemeasurements and the known locations of the measured network nodes(i.e., the base station(s) 402 or antenna(s) that transmitted thereference RF signals that the UE 404 measured), the UE 404 or thelocation server can determine the distance between the UE 404 and themeasured network nodes and thereby calculate the location of the UE 404.

The term “position estimate” is used herein to refer to an estimate of aposition for a UE 404, which may be geographic (e.g., may comprise alatitude, longitude, and possibly altitude) or civic (e.g., may comprisea street address, building designation, or precise point or area withinor nearby to a building or street address, such as a particular entranceto a building, a particular room or suite in a building, or a landmarksuch as a town square). A position estimate may also be referred to as a“location,” a “position,” a “fix,” a “position fix,” a “location fix,” a“location estimate,” a “fix estimate,” or by some other term. The meansof obtaining a location estimate may be referred to generically as“positioning,” “locating,” or “position fixing.” A particular solutionfor obtaining a position estimate may be referred to as a “positionsolution.” A particular method for obtaining a position estimate as partof a position solution may be referred to as a “position method” or as a“positioning method.”

The term “base station” may refer to a single physical transmissionpoint or to multiple physical transmission points that may or may not beco-located. For example, where the term “base station” refers to asingle physical transmission point, the physical transmission point maybe an antenna of the base station (e.g., base station 402) correspondingto a cell of the base station. Where the term “base station” refers tomultiple co-located physical transmission points, the physicaltransmission points may be an array of antennas (e.g., as in a MIMOsystem or where the base station employs beamforming) of the basestation. Where the term “base station” refers to multiple non-co-locatedphysical transmission points, the physical transmission points may be aDistributed Antenna System (DAS) (a network of spatially separatedantennas connected to a common source via a transport medium) or aRemote Radio Head (RRH) (a remote base station connected to a servingbase station). Alternatively, the non-co-located physical transmissionpoints may be the serving base station receiving the measurement reportfrom the UE (e.g., UE 404) and a neighbor base station whose referenceRF signals the UE is measuring. Thus, FIG. 4 illustrates an aspect inwhich base stations 402 a and 402 b form a DAS/RRH 420. For example, thebase station 402 a may be the serving base station of the UE 404 and thebase station 402 b may be a neighbor base station of the UE 404. Assuch, the base station 402 b may be the RRH of the base station 402 a.The base stations 402 a and 402 b may communicate with each other over awired or wireless link 422.

To accurately determine the position of the UE 404 using the OTDOAsand/or RSTDs between RF signals received from pairs of network nodes,the UE 404 needs to measure the reference RF signals received over theLOS path (or the shortest NLOS path where an LOS path is not available),between the UE 404 and a network node (e.g., base station 402, antenna).However, RF signals travel not only by the LOS/shortest path between thetransmitter and receiver, but also over a number of other paths as theRF signals spread out from the transmitter and reflect off other objectssuch as hills, buildings, water, and the like on their way to thereceiver. Thus, FIG. 4 illustrates a number of LOS paths 410 and anumber of NLOS paths 412 between the base stations 402 and the UE 404.Specifically, FIG. 4 illustrates base station 402 a transmitting over anLOS path 410 a and an NLOS path 412 a, base station 402 b transmittingover an LOS path 410 b and two NLOS paths 412 b, base station 402 ctransmitting over an LOS path 410 c and an NLOS path 412 c, and basestation 402 d transmitting over two NLOS paths 412 d. As illustrated inFIG. 4, each NLOS path 412 reflects off some object 430 (e.g., abuilding). As will be appreciated, each LOS path 410 and NLOS path 412transmitted by a base station 402 may be transmitted by differentantennas of the base station 402 (e.g., as in a MIMO system), or may betransmitted by the same antenna of a base station 402 (therebyillustrating the propagation of an RF signal). Further, as used herein,the term “LOS path” refers to the shortest path between a transmitterand receiver, and may not be an actual LOS path, but rather, theshortest NLOS path.

In an aspect, one or more of base stations 402 may be configured to usebeamforming to transmit RF signals. In that case, some of the availablebeams may focus the transmitted RF signal along the LOS paths 410 (e.g.,the beams produce highest antenna gain along the LOS paths) while otheravailable beams may focus the transmitted RF signal along the NLOS paths412. A beam that has high gain along a certain path and thus focuses theRF signal along that path may still have some RF signal propagatingalong other paths; the strength of that RF signal naturally depends onthe beam gain along those other paths. An “RF signal” comprises anelectromagnetic wave that transports information through the spacebetween the transmitter and the receiver. As used herein, a transmittermay transmit a single “RF signal” or multiple “RF signals” to areceiver. However, as described further below, the receiver may receivemultiple “RF signals” corresponding to each transmitted RF signal due tothe propagation characteristics of RF signals through multipathchannels.

Where a base station 402 uses beamforming to transmit RF signals, thebeams of interest for data communication between the base station 402and the UE 404 will be the beams carrying RF signals that arrive at UE404 with the highest signal strength (as indicated by, e.g., theReceived Signal Received Power (RSRP) or SINR in the presence of adirectional interfering signal), whereas the beams of interest forposition estimation will be the beams carrying RF signals that excitethe shortest path or LOS path (e.g., an LOS path 410). In some frequencybands and for antenna systems typically used, these will be the samebeams. However, in other frequency bands, such as mmW, where typically alarge number of antenna elements can be used to create narrow transmitbeams, they may not be the same beams. As described below with referenceto FIG. 5, in some cases, the signal strength of RF signals on the LOSpath 410 may be weaker (e.g., due to obstructions) than the signalstrength of RF signals on an NLOS path 412, over which the RF signalsarrive later due to propagation delay.

FIG. 5 illustrates an exemplary wireless communications system 500according to various aspects of the disclosure. In the example of FIG.5, a UE 504, which may correspond to UE 404 in FIG. 4, is attempting tocalculate an estimate of its position, or to assist another entity(e.g., a base station or core network component, another UE, a locationserver, a third party application, etc.) to calculate an estimate of itsposition. The UE 504 may communicate wirelessly with a base station 502,which may correspond to one of base stations 402 in FIG. 4, using RFsignals and standardized protocols for the modulation of the RF signalsand the exchange of information packets.

As illustrated in FIG. 5, the base station 502 is utilizing beamformingto transmit a plurality of beams 511-515 of RF signals. Each beam511-515 may be formed and transmitted by an array of antennas of thebase station 502. Although FIG. 5 illustrates a base station 502transmitting five beams 511-515, as will be appreciated, there may bemore or fewer than five beams, beam shapes such as peak gain, width, andside-lobe gains may differ amongst the transmitted beams, and some ofthe beams may be transmitted by a different base station.

A beam index may be assigned to each of the plurality of beams 511-515for purposes of distinguishing RF signals associated with one beam fromRF signals associated with another beam. Moreover, the RF signalsassociated with a particular beam of the plurality of beams 511-515 maycarry a beam index indicator. A beam index may also be derived from thetime of transmission, e.g., frame, slot and/or OFDM symbol number, ofthe RF signal. The beam index indicator may be, for example, a three-bitfield for uniquely distinguishing up to eight beams. If two different RFsignals having different beam indices are received, this would indicatethat the RF signals were transmitted using different beams. If twodifferent RF signals share a common beam index, this would indicate thatthe different RF signals are transmitted using the same beam. Anotherway to describe that two RF signals are transmitted using the same beamis to say that the antenna port(s) used for the transmission of thefirst RF signal are spatially quasi-collocated with the antenna port(s)used for the transmission of the second RF signal.

In the example of FIG. 5, the UE 504 receives an NLOS data stream 523 ofRF signals transmitted on beam 513 and an LOS data stream 524 of RFsignals transmitted on beam 514. Although FIG. 5 illustrates the NLOSdata stream 523 and the LOS data stream 524 as single lines (dashed andsolid, respectively), as will be appreciated, the NLOS data stream 523and the LOS data stream 524 may each comprise multiple rays (i.e., a“cluster”) by the time they reach the UE 504 due, for example, to thepropagation characteristics of RF signals through multipath channels.For example, a cluster of RF signals is formed when an electromagneticwave is reflected off of multiple surfaces of an object, and reflectionsarrive at the receiver (e.g., UE 504) from roughly the same angle, eachtravelling a few wavelengths (e.g., centimeters) more or less thanothers. A “cluster” of received RF signals generally corresponds to asingle transmitted RF signal.

In the example of FIG. 5, the NLOS data stream 523 is not originallydirected at the UE 504, although, as will be appreciated, it could be,as are the RF signals on the NLOS paths 412 in FIG. 4. However, it isreflected off a reflector 540 (e.g., a building) and reaches the UE 504without obstruction, and therefore, may still be a relatively strong RFsignal. In contrast, the LOS data stream 524 is directed at the UE 504but passes through an obstruction 530 (e.g., vegetation, a building, ahill, a disruptive environment such as clouds or smoke, etc.), which maysignificantly degrade the RF signal. As will be appreciated, althoughthe LOS data stream 524 is weaker than the NLOS data stream 523, the LOSdata stream 524 will arrive at the UE 504 before the NLOS data stream523 because it follows a shorter path from the base station 502 to theUE 504.

As noted above, the beam of interest for data communication between abase station (e.g., base station 502) and a UE (e.g., UE 504) is thebeam carrying RF signals that arrives at the UE with the highest signalstrength (e.g., highest RSRP or SINR), whereas the beam of interest forposition estimation is the beam carrying RF signals that excite the LOSpath and that has the highest gain along the LOS path amongst all otherbeams (e.g., beam 514). That is, even if beam 513 (the NLOS beam) wereto weakly excite the LOS path (due to the propagation characteristics ofRF signals, even though not being focused along the LOS path), that weaksignal, if any, of the LOS path of beam 513 may not be as reliablydetectable (compared to that from beam 514), thus leading to greatererror in performing a positioning measurement.

While the beam of interest for data communication and the beam ofinterest for position estimation may be the same beams for somefrequency bands, for other frequency bands, such as mmW, they may not bethe same beams. As such, referring to FIG. 5, where the UE 504 isengaged in a data communication session with the base station 502 (e.g.,where the base station 502 is the serving base station for the UE 504)and not simply attempting to measure reference RF signals transmitted bythe base station 502, the beam of interest for the data communicationsession may be the beam 513, as it is carrying the unobstructed NLOSdata stream 523. The beam of interest for position estimation, however,would be the beam 514, as it carries the strongest LOS data stream 524,despite being obstructed.

FIG. 6A is a graph 600A showing the RF channel response at a receiver(e.g., UE 504) over time according to aspects of the disclosure. Underthe channel illustrated in FIG. 6A, the receiver receives a firstcluster of two RF signals on channel taps at time T1, a second clusterof five RF signals on channel taps at time T2, a third cluster of fiveRF signals on channel taps at time T3, and a fourth cluster of four RFsignals on channel taps at time T4. In the example of FIG. 6A, becausethe first cluster of RF signals at time T1 arrives first, it is presumedto be the LOS data stream (i.e., the data stream arriving over the LOSor the shortest path), and may correspond to the LOS data stream 524.The third cluster at time T3 is comprised of the strongest RF signals,and may correspond to the NLOS data stream 523. Seen from thetransmitter's side, each cluster of received RF signals may comprise theportion of an RF signal transmitted at a different angle, and thus eachcluster may be said to have a different angle of departure (AoD) fromthe transmitter. FIG. 6B is a diagram 600B illustrating this separationof clusters in AoD. The RF signal transmitted in AoD range 602 a maycorrespond to one cluster (e.g., “Cluster1”) in FIG. 6A, and the RFsignal transmitted in AoD range 602 b may correspond to a differentcluster (e.g., “Cluster3”) in FIG. 6A. Note that although AoD ranges ofthe two clusters depicted in FIG. 6B are spatially isolated, AoD rangesof some clusters may also partially overlap even though the clusters areseparated in time. For example, this may arise when two separatebuildings at same AoD from the transmitter reflect the signal towardsthe receiver. Note that although FIG. 6A illustrates clusters of two tofive channel taps, as will be appreciated, the clusters may have more orfewer than the illustrated number of channel taps.

As in the example of FIG. 5, the base station may utilize beamforming totransmit a plurality of beams of RF signals such that one of the beams(e.g., beam 514) is directed at the AoD range 602 a of the first clusterof RF signals, and a different beam (e.g., beam 513) is directed at theAoD range 602 b of the third cluster of RF signals. The signal strengthof clusters in post-beamforming channel response (i.e., the channelresponse when the transmitted RF signal is beamformed instead ofomni-directional) will be scaled by the beam gain along the AoD of theclusters. In that case, the beam of interest for positioning would bethe beam directed at the AoD of the first cluster of RF signals, as theyarrive first, and the beam of interest for data communications may bethe beam directed at the AoD of the third cluster of RF signals, as theyare the strongest.

In general, when transmitting an RF signal, the transmitter does notknow what path it will follow to the receiver (e.g., UE 504) or at whattime it will arrive at the receiver, and therefore transmits the RFsignal on different antenna ports with an equal amount of energy.Alternatively, the transmitter may beamform the RF signal in differentdirections over multiple transmission occasions and obtain measurementfeedback from the receiver to explicitly or implicitly determine radiopaths.

Note that although the techniques disclosed herein have generally beendescribed in terms of transmissions from a base station to a UE, as willbe appreciated, they are equally applicable to transmissions from a UEto a base station where the UE is capable of MIMO operation and/orbeamforming. Also, while beamforming is generally described above incontext with transmit beamforming, receive beamforming may also be usedin conjunction with the above-noted transmit beamforming in certainembodiments.

As discussed above, in some frequency bands, the shortest path (whichmay, as noted above, be a LOS path or the shortest NLOS path) may beweaker than an alternative longer (NLOS) path (over which the RF signalarrives later due to propagation delay). Thus, where a transmitter usesbeamforming to transmit RF signals, the beam of interest for datacommunication—the beam carrying the strongest RF signals—may bedifferent from the beam of interest for position estimation—the beamcarrying the RF signals that excite the shortest detectable path. Assuch, it would be beneficial for the receiver to identify and report thebeam of interest for position estimation to the transmitter to enablethe transmitter to subsequently modify the set of transmitted beams toassist the receiver to perform a position estimation.

FIG. 7 illustrates an exemplary method according to an aspect of thedisclosure. At 702, a second node 703 (referred to as the “transmitter”)transmits a set of beams 705, 707, and 709 to a first node 701 (referredto as the “receiver”). In an aspect, the first node 701 may be a UE,such as UE 350/404/504, and the second node 703 may be a base station,such as base station 310/402/502. However, in an aspect, the first node701 may be a base station and the second node 703 may be a UE, or boththe first node 701 and the second node 703 may be UEs or base stations.As yet another alternative, the second node 703 may be a single antennaor antenna array of a base station or UE capable of beamforming.

In the example of FIG. 7, the second node 703 transmits a set of threebeams 705, 707, and 709. These beams may be transmitted simultaneouslybut distinguishable in frequency and/or code domain. Alternatively,these beams may be transmitted sequentially. The second node 703 maytransmit the beams 705, 707, and 709 at different AoDs, as illustratedabove in FIGS. 5 and 6B. In the example of FIG. 7, the beam 707(illustrated as a straight line) may follow the shortest path (e.g., LOSpath or shortest NLOS path when the LOS path is undetectable due toobstruction) from the second node 703 to the first node 701, and thebeams 705 and 709 may follow longer (e.g., NLOS) paths from the secondnode 703 to the first node 701. As will be appreciated, there may bemore or fewer than three beams, as shown above in the examples of FIGS.4 and 5. In an aspect, the beams 705, 707, and 709 may carrysynchronization signals, such as Synchronization Signal (SS) or PBCHblocks, CSI reference signals, positioning reference signals, cellreference signals, sounding reference signals, random access preamble,or the like.

At 704, the first node 701 receives the beams 705, 707, and 709. At 706,the first node 701 determines the time of arrival of each beam 705, 707,and 709. In an aspect, the first node 701 may determine the time ofarrival of a beam as the time at which the first node 701 detects thefirst (or earliest) channel tap of the radio channel between the nodes,where the channel is estimated from the received RF signal of a beam705, 707, or 709. For example, the first node 701 may correlate thereceived signal of a beam with the (conjugate of) known transmitted RFsignals and determine the channel taps from the peaks of correlation.The first node 701 may further estimate noise and eliminate channel tapsthat are less reliable for being comparable to a noise floor. The firstnode 701 may further employ techniques to eliminate spurious side peaksaround strong channel taps, where the spurious side peaks are well knownto arise from bandlimited reception at the first node 701. Forsimplicity, the first channel tap of an RF signal of a beam may also bereferred to as the first channel tap of a beam.

At 708, the first node 701 identifies one or more beams of interest fromthe set of beams 705, 707, and 709 based on the times of arrivaldetermined at 706. As noted above, in some frequency bands wheretypically deployed antenna systems do not create narrow enough beams,the beam(s) of interest would be the beam(s) 705, 707, and/or 709carrying RF signals with the highest received signal strength at thefirst node 701 (e.g., RSRP or SINR), as these would also be the beam(s)following the shortest path to the first node 701. However, as discussedabove, in some frequency bands, such as mmW, the beam carrying RFsignals with the highest received signal strength may not be the bestbeam for positioning operations as it may not follow the shortestdetectable path to the first node 701. As such, rather than select thebeam(s) carrying RF signals with the highest received signal strength,the first node 701 instead identifies one or more of the earliestarriving beams of the beams 705, 707, and 709 as the one or more beamsof interest. For example, the one or more beams of interest may be thebeam 705, 707, or 709 with the first detected channel tap. Or the one ormore beams of interest may be the N (greater than 1, e.g., 2) beams withthe earliest detected channel taps. Or the one or more beams of interestmay be the beam, or N beams, whose first detected channel tap is withina predetermined delay (e.g., 10 nanoseconds) from the first detected tapof the beam with the earliest detected first tap. At the speed of lightof about 0.3 meters per nanosecond (ns), an error or ambiguity of 10 nsin time of arrival corresponds to a positioning/distancing error ofapproximately three meters. Therefore, the delay may be determined bythe desired accuracy or achievable accuracy in the presence of otherlimiting factors, such as signal pulse width (related to signalbandwidth). The delay parameter may be provided to the second node 703by the first node 701, or determined by the first node 701 itself andreported to the second node 703. In an aspect, where the first node 701is a UE, the second node 703 (a base station) may command the first node701 to report the beams of interest for position estimation (instead ofthe beams with the highest received signal strength, as isconventionally done), the number N of beams to report, and/or the“delay” parameter for selecting N beams.

At 710, the first node 701 generates a report containing identifiers(e.g., beam indices) of the one or more beams of interest identified at708. At 712, the first node 701 transmits the report to the second node703.

At 714, the second node 703 receives the report. The first node 701 maytransmit at 712, and the second node 703 may receive at 714, the reportover a wireless interface, such as a communication link 120 in FIG. 1.The reception point of the second node 703 that receives the report mayor may not be collocated with the transmission point(s) of second node703 from which the beams 705, 707, 709 are transmitted. For example, thereception point of the second node 703 that receives the report may beassigned a different cell identity than that of the transmission pointof the node that transmits the beams. The reception point may be theserving cell and the transmission point may be a non-serving cell, suchas a neighbor cell.

At 716, the second node 703 can select a second set of beams fortransmission based on the received report. For example, where the firstnode 701 is attempting to perform a position estimation and theidentified beam(s) are cell synchronization beam(s), the second node 703can update the beam(s) identified in the report to transmit positioningRF signals, such as PRS or CSI-RS. Generally, beams transmittingsynchronization signals are broader (less focused) than beamstransmitting reference RF signals (e.g., CSI-RS). As such, in an aspect,the second node 703 may also transmit one or more finer (more focused)beams around the beam(s) identified in the report, after they have beenmodified to transmit reference RF signals. More specifically, the secondnode 703 may narrow the focus of the identified beam(s) and transmit oneor more additional narrowly focused beams in the direction of theidentified beam(s).

As another example, again where the first node 701 is attempting toperform a position estimation and the identified beam(s) are cellsynchronization beam(s), the second node 703 can transmit one or morebeams carrying positioning RF signals in the direction of the beam(s)identified in the report, without modifying the beam(s) identified inthe report. Thus, in an aspect, the transmission of beams 705, 707, and709 at 702 may be periodic (e.g., a broadcast for the benefit of all UEsserved by the second node, where the second node is a base station), andthe selection of beams at 716 may be for the transmission of specificpositioning beacons for the benefit of the first node only, and may betransmitted at a different periodicity or aperiodically.

In an aspect, where the first node 701 is a base station, then reportingthe beam indices at 710 and 712 means that the first node 701 asks thesecond node 703 (the UE) to transmit further reference beams based onthe report. For example, the request may be to transmit the reportedbeams again, or to transmit finer beams around the reported beams. Thus,the operation at 708 is a way to shortlist the beam(s) of interest andsubsequently to use the shortlisted beam(s) for on-going positionestimation while discarding the ‘uninteresting’ beams.

At 718, the second node 703 transmits the second set of beams, here,beams 711 and 713. As discussed above, the beams 711 and 713 maycorrespond to two of the beams 705, 707, and 709 (where the reportreceived at 714 identifies two of beams 705, 707, and 709), but modifiedto transmit reference RF signals (e.g., PRS, CRS). Alternatively, beams711 and 713 may correspond to one of beams 705, 707, and 709 modified totransmit reference RF signals, and an additional beam transmittingreference RF signals in the direction of the beams identified in thereport received at 714. In yet another aspect, beams 711 and 713 may betwo new beams transmitting reference RF signals in the direction of thebeams identified in the report received at 714. In an aspect, althoughnot illustrated, prior to transmitting the beams 711 and 713, the secondnode 703 may transmit an indication of which beams it has selected fortransmission at 718.

In the example of FIG. 7, there are two beams (711 and 713) transmittedat 718. However, as will be appreciated, this is merely an example, andthere may be more or fewer beams transmitted at 718. In addition, inFIG. 7, beam 711 is illustrated as following a LOS path and beam 713 isillustrated as following an NLOS path (i.e., as reflected off anobject). However, as will be appreciated, both beams 711 and 713 mayfollow a LOS path, or both may be reflected.

At 720, the first node 701 receives the beams 711 and 713. The firstnode 701 may perform the process of FIG. 7 with a plurality of secondnodes, including the second node 703, in order to receive a sufficientnumber of shortest path beams that can be accurately measured tocalculate, or assist the calculation of, a position estimate. Forexample, to perform a single OTDOA measurement, the first node 701 needsto measure reference RF signals from at least two second nodes. Thefirst node 701 may make multiple OTDOA measurements to improve accuracyof a position estimate of the first node 701.

FIG. 8 illustrates an exemplary method 800 for determining a positionestimate of a UE in accordance with an embodiment of the disclosure. Themethod 800 may be performed by a UE 805, which may correspond to any oneof UEs 104, 240 or 350 as described above with respect to FIGS. 1-3A.

Referring to FIG. 8, at 802, the UE 805 (e.g., antenna(s) 352,receiver(s) 354, and/or RX processor 356) receives, from a networkentity, at least one base station almanac (BSA) message that indicates(i) a set of transmission point locations associated with at least onebase station, the set of transmission point locations including at leastone transmission point location of a base station that is based upon aplurality of different transmission point locations associated with thebase station, and (ii) a mapping of each of a plurality of beams to theat least one transmission point location. In an example, the networkcomponent from which the at least one BSA message is receivedcorresponds to the base station itself. In an alternative example, theat least one BSA message may be received from a server, such as thelocation server 230, although the base station may facilitate thewireless transmission of the at least one BSA message even if the basestation does not act as the originating source of the at least one BSAmessage.

FIG. 9 illustrates an arrangement 900 of beams being transmitted by abase station (BS₁) in accordance with aspects of the disclosure. In FIG.9, the base station is provisioned with three distinct transmissionpoint locations denoted as A, B and C, which are connected to each othervia a backhaul link. In particular, the transmission point locations A,B and C correspond to different antennas (or antenna arrays) throughwhich the base station can transmit beams of RF signals. Theserespective antennas may be referred to as remote radio heads (RRHs) orremote radio units (RRUs). In the embodiment of FIG. 9, the base stationcollectively transmits eight (8) total beams indexed with beam indices 1. . . 8 from transmission point locations A, B and C, as follows:

TABLE 1 Mapping of Beams to Different Transmission Point Locations forBase Station Transmission Point Beam Index Location 1 A 2 A 3 B 4 B 5 A6 C 7 C 8 B

The information noted above in Table 1 may be determined in advance andstored in a BSA database (more specifically, in a BSA record for thebase station), which is accessible to the network entity via a lookupoperation.

Turning back to 802 of FIG. 8, in an example, the at least one BSAmessage may convey some or all of the information contained in Table 1.In a first example, the at least one BSA message may indicate thespecific locations of each of the transmission point locations A, B andC along with the associated beams being transmitted at each transmissionpoint location. In a second example, instead of each beam beingindividually mapped to a particular transmission point location, thebeams may instead be mapped to a representative single representativetransmission point location that is based upon the transmission pointlocations A, B and C. This representative single representativetransmission point location may be denoted as transmission pointlocation A+B+C. For example, the transmission point location A+B+C maybe averaged (e.g., weighted average, etc.) in some manner from thedifferent transmission point locations A, B and C. In an alternativeexample, the transmission point location A+B+C may correspond to one ofthe different transmission point locations A, B and C. An examplemapping of beams 1 . . . 8 in FIG. 9 to transmission point locations A,B and C is as follows:

TABLE 2 Mapping of Beams to Representative Transmission Point Locationfor Base Station Transmission Point Beam Index Location 1 A + B + C 2A + B + C 3 A + B + C 4 A + B + C 5 A + B + C 6 A + B + C 7 A + B + C 8A + B + C

The information noted above in Table 2 may be determined in advance andstored in a BSA database (more specifically, in a BSA record for thebase station), which is accessible to the network entity via a lookupoperation.

In a third example, instead of a single representative transmissionpoint location being used for all beams transmitted by a particular basestation, representative transmission point locations may be used forparticular subsets of beams. For example, certain beams with the samebeam index may be transmitted from different transmission pointlocations. In terms of beam mapping, the UE can be notified of eachtransmission point location to which this beam is mapped, or to arepresentative transmission point location based on the transmissionpoint locations. Consider a scenario as shown in Table 1 above, exceptthe beam with beam index 1 is transmitted from both A and B, and thebeam with beam index 8 is transmitted from both B and C, and shown inTable 3:

TABLE 3 Mapping of Beams to Different Transmission Point Locations forBase Station Transmission Point Beam Index Location 1 A + B 2 A 3 B 4 B5 A 6 C 7 C 8 B + C

In this case, the BSA message can be configured to notify the UE thatbeam index 1 is transmitted from both A and B by indicating bothtransmission point locations, or alternatively can identify a locationthat approximates (e.g., averages) the transmission point locations of Aand B. Likewise, the BSA message can be configured to notify the UE thatbeam index 8 is transmitted from both B and C by indicating bothtransmission point locations, or alternatively can identify a locationthat approximates (e.g., averages) the transmission point locations of Band C. The information noted above in Table 3 may be determined inadvance and stored in a BSA database (more specifically, in a BSA recordfor the base station), which is accessible to the network entity via alookup operation.

Referring to FIG. 8, at 804, at the UE 805 (e.g., antenna(s) 352,receiver(s) 354, and/or RX processor 356) optionally receives, from thebase station, the plurality of beams in accordance with the mapping. At806, the UE 805 (e.g., controller/processor 359) optionally estimates aposition of the UE based at least in part upon (i) one or moremeasurements performed by the UE on one or more of the plurality ofbeams and (ii) the at least one transmission point location to which theone or more beams are mapped.

Referring to 802 of FIG. 8, in an example, the plurality of beamsreceived at the UE 805 may carry synchronization signal blocks (SSBs).In an example specific to 5G NR, SSBs may be transmitted using up to 64different transmission beams or transmission precoders, so a number ofdifferent cells and/or transmission point locations can use SSBs aspositioning beacons without a conflict. Other beamswept signals that canbe used as positioning signals may include reference signals (RSs), suchas a PRS, a UE-specific or cell-specific CSI-RS, and so on.

In an example, the one or more measurements used to estimate the UEposition at 806 may correspond to Time of Arrival (ToA) measurements.The ToA measurements may be used to compute OTDOA between ToA of beamstransmitted from different transmission locations, where the OTDOAmeasurements are subsequently used to derive the UE position estimate.Similarly, the ToA measurements may be used as part of round trippropagation time (RTT) estimation procedure(s) between the UE 805 andthe transmission location points of the base station, after which thecalculated RTT(s) are used to derive the UE position estimate (e.g., viamultilateration, such as trilateration). For example, if the at leastone transmission location point used at 806 is the plurality ofdifferent transmission location points, the UE determines a mapping ofeach beam to a respective transmission location point based on the atleast one BSA message, and then derives a different RTT to eachtransmission location point based on the associated ToA measurements forthat transmission location point's mapped beam(s). UE may not compute aToA for a transmission location point from which the UE does not detecta beam (or does not detect the beam reliably enough) for estimating ToA.In another example, if the at least one transmission location point usedat 806 is the single representative transmission location point, the UEderives a single RTT to the single representative transmission locationpoint based on the associated ToA measurements for the plurality ofbeams (e.g., as if each beam was transmitted from the singlerepresentative transmission location point, irrespective of whichtransmission location point the beams were actually transmitted from).

Referring to 806 of FIG. 8, in a further example, assume that the UE 805cannot ascertain the transmission point location to which a particularbeam or group of beams is mapped. In this case, the UE 805 may determinemultiple candidate transmission point locations to which at least one ofthe one or more beams is mapped. For example, as noted above withrespect to Table 3, the UE 805 may be notified via the BSA message(s)that a particular beam is being transmitted from multiple transmissionpoint locations. The UE 805 may then estimate multiple candidateposition estimates of the UE 805 at 806 based on the multiple candidatetransmission point locations. For example, the UE 805 may select onetransmission point location from the multiple candidate transmissionpoint locations, and assume that the detected ToA is based on the signalreceived from the selected transmission point location. That is, in themultilateration procedure, the location of the selected transmissionpoint is used as the only transmission location of the signal and acandidate position of the UE 805 estimated under this assumption. Inthis manner, the UE 805 can calculate a candidate position estimatecorresponding to each candidate transmission point location. The UE 805may then derive the position estimate for the UE based on the multiplecandidate position estimates. For example, the position estimatederivation may include (i) averaging of the multiple candidate positionestimates, or (ii) selecting the candidate position estimate that ismost congruent with one or more other positioning measurements such asToA measurements from other known transmission locations and previouslyestimated position estimates for the UE. For example, the most congruentcandidate position estimate may correspond to the position estimate thatis geographically closest to one or more previous position estimates forthe UE, the position estimate that tracks closest to a trajectory atwhich the UE has been logged as moving, and so on. Similarly, the UE 805may employ statistical techniques for outlier elimination such as RANSACalgorithm to eliminate false hypotheses on the candidate transmissionpoint locations when a beam is transmitted from multiple transmissionpoints locations.

FIG. 10 illustrates an exemplary method 1000 for transmitting locationinformation pertaining to a plurality of different transmission pointlocations associated with a base station in accordance with anembodiment of the disclosure. The method 1000 may be performed by anetwork entity 1005, which may correspond to a base station such as anyof base stations 102, 222, 224, 31, 402 a-402 d, 502, or alternativelyto a server such as 230 or 300B.

Referring to FIG. 10, at 1002, the network entity 1005 (e.g., antenna(s)320, transmitter(s) 318, and/or TX processor 316, network access ports304B) transmits, to a UE, at least one BSA message that indicates (i) aset of transmission point locations associated with at least one basestation, the set of transmission point locations including at least onetransmission point location of a base station that is based upon aplurality of different transmission point locations associated with thebase station, and (ii) a mapping of each of a plurality of beams to theat least one transmission point location. In an example, the at leastone BSA message transmitted at 1002 corresponds to the at least one BSAmessage received by the UE 805 at 802 of FIG. 8.

Referring to FIG. 10, at 1004, the network entity 1005 (e.g., antenna(s)320, transmitter(s) 318, and/or TX processor 316) optionally transmitsthe plurality of beams from the at least one transmission point locationof the base station in accordance with the mapping. The transmission at1004 may be performed by the network entity 1005 if the network entity1005 corresponds to the base station. However, as noted above, thenetwork entity 1005 could also correspond to a server that is separatefrom the base station transmitting the beams, in which case 1004 is notperformed by the network entity 1005. In an example, the beams that areoptionally transmitted by the network entity 1005 at 1004 correspond tothe beams received by the UE 805 at 804 of FIG. 8.

FIGS. 11-12 illustrate example implementations of the processes of FIGS.8 and 10 in accordance with embodiments of the disclosure.

Referring to FIG. 11, assume that 702-708 of FIG. 7 are performed. After708 of FIG. 7, at 1102, the UE 805 transmits, to the network entity1005, a request for location information related to the base stationalong with an indication of the identified beam(s) of interest from 708.The network entity 1005 receives the request at 1104. At 1106, thenetwork entity 1005 transmits at least one BSA message includingtransmission point location(s) that are mapped to the identified beam(s)of interest, along with the associated mapping information. At 1108, theUE 805 receives the at least one BSA message. The BSA message(s)exchanged at 1106-1108 may correspond to the BSA message(s) exchanged at802 of FIG. 8 or 1002 of FIG. 10. So, the process of FIG. 11demonstrates that the BSA message(s) may be exchanged responsive to arequest from the UE 805, in particular, a request that is both basestation-specific and beam-specific.

In other embodiments, the UE 805 need not specify any particular beam(s)of interest as in FIG. 11. Rather, the UE 805 need only identify thebase station for which location information is needed, and the networkentity 1005 can send BSA message(s) that convey all the transmissionpoint location(s) that are mapped to any beam being transmitted by thatbase station, along with the associated mapping information. Moreover,the network entity 1005 may send transmission point location informationfor one or more other base stations as well, either in the same BSAmessage(s) or in different BSA message(s).

Referring to FIG. 12, assume that 1102-1108 of FIG. 11 are performed.After 1108 of FIG. 11, at 1202, the base station (denoted as basestation 1203 in FIG. 12) transmits, to the UE 805, a set of beamsincluding beams 1205, 1207 and 1209 in accordance with the mapping thatis conveyed by the BSA message(s) from 1106-1108. The set of beams isreceived by the UE 805 at 1204. The beams exchanged at 1202-1204 maycorrespond to the beams exchanged at 804 of FIG. 8 or 1004 of FIG. 10.At 1212, the UE 805 estimates its position based on measurement(s)performed by the UE 805 on one or more beams from the set of beams aswell as the at least one transmission point location (e.g., a pluralityof different beam-mapped transmission point locations or a singlerepresentative transmission point location for the base station as notedabove).

Those skilled in the art will appreciate that information and signalsmay be represented using any of a variety of different technologies andtechniques. For example, data, instructions, commands, information,signals, bits, symbols, and chips that may be referenced throughout theabove description may be represented by voltages, currents,electromagnetic waves, magnetic fields or particles, optical fields orparticles, or any combination thereof.

Further, those skilled in the art will appreciate that the variousillustrative logical blocks, modules, circuits, and algorithm stepsdescribed in connection with the aspects disclosed herein may beimplemented as electronic hardware, computer software, or combinationsof both. To clearly illustrate this interchangeability of hardware andsoftware, various illustrative components, blocks, modules, circuits,and steps have been described above generally in terms of theirfunctionality. Whether such functionality is implemented as hardware orsoftware depends upon the particular application and design constraintsimposed on the overall system. Skilled artisans may implement thedescribed functionality in varying ways for each particular application,but such implementation decisions should not be interpreted to departfrom the scope of the various aspects described herein.

The various illustrative logical blocks, modules, and circuits describedin connection with the aspects disclosed herein may be implemented orperformed with a general purpose processor, a digital signal processor(DSP), an application specific integrated circuit (ASIC), a fieldprogrammable gate array (FPGA) or other programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof designed to perform the functions described herein.A general purpose processor may be a microprocessor, but in thealternative, the processor may be any conventional processor,controller, microcontroller, or state machine. A processor may also beimplemented as a combination of computing devices (e.g., a combinationof a DSP and a microprocessor, a plurality of microprocessors, one ormore microprocessors in conjunction with a DSP core, or other suchconfigurations).

The methods, sequences, and/or algorithms described in connection withthe aspects disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.A software module may reside in RAM, flash memory, ROM, EPROM, EEPROM,registers, hard disk, a removable disk, a CD-ROM, or any other form ofnon-transitory computer-readable medium known in the art. An exemplarynon-transitory computer-readable medium may be coupled to the processorsuch that the processor can read information from, and write informationto, the non-transitory computer-readable medium. In the alternative, thenon-transitory computer-readable medium may be integral to theprocessor. The processor and the non-transitory computer-readable mediummay reside in an ASIC. The ASIC may reside in a user device (e.g., a UE)or a base station. In the alternative, the processor and thenon-transitory computer-readable medium may be discrete components in auser device or base station.

In one or more exemplary aspects, the functions described herein may beimplemented in hardware, software, firmware, or any combination thereof.If implemented in software, the functions may be stored on ortransmitted over as one or more instructions or code on a non-transitorycomputer-readable medium. Computer-readable media may include storagemedia and/or communication media including any non-transitory mediumthat may facilitate transferring a computer program from one place toanother. A storage media may be any available media that can be accessedby a computer. By way of example, and not limitation, suchcomputer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or otheroptical disk storage, magnetic disk storage or other magnetic storagedevices, or any other medium that can be used to carry or store desiredprogram code in the form of instructions or data structures and that canbe accessed by a computer. Also, any connection is properly termed acomputer-readable medium. For example, if the software is transmittedfrom a website, server, or other remote source using a coaxial cable,fiber optic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave, then the coaxial cable, fiber opticcable, twisted pair, DSL, or wireless technologies such as infrared,radio, and microwave are included in the definition of a medium. Theterm disk and disc, which may be used interchangeably herein, includesCD, laser disc, optical disc, DVD, floppy disk, and Blu-ray discs, whichusually reproduce data magnetically and/or optically with lasers.Combinations of the above should also be included within the scope ofcomputer-readable media.

While the foregoing disclosure shows illustrative aspects, those skilledin the art will appreciate that various changes and modifications couldbe made herein without departing from the scope of the disclosure asdefined by the appended claims. Furthermore, in accordance with thevarious illustrative aspects described herein, those skilled in the artwill appreciate that the functions, steps, and/or actions in any methodsdescribed above and/or recited in any method claims appended hereto neednot be performed in any particular order. Further still, to the extentthat any elements are described above or recited in the appended claimsin a singular form, those skilled in the art will appreciate thatsingular form(s) contemplate the plural as well unless limitation to thesingular form(s) is explicitly stated.

What is claimed is:
 1. A method of operating a user equipment (UE),comprising: receiving, from a network entity, location assistance datathat indicates (i) a set of antenna locations associated with at leastone base station, the set of antenna locations including at least oneantenna location of a base station, the at least one antenna locationincluding a plurality of different antenna location coordinate valuesstored in one or more records associated with the base station, a singleantenna location that is representative of multiple different antennalocation coordinate values stored in at least one record associated withthe base station, or a combination thereof, and (ii) a mapping of eachof a plurality of beams to the at least one antenna location; receiving,from the base station, the plurality of beams in accordance with themapping; and performing one or more measurements on one or more of theplurality of beams.
 2. The method of claim 1, further comprising:estimating a position of the UE based at least in part upon (i) the oneor more measurements performed by the UE on the one or more of theplurality of beams and (ii) the at least one antenna location to whichthe one or more beams are mapped.
 3. The method of claim 1, wherein theat least one antenna location includes the plurality of differentantenna location coordinate values.
 4. The method of claim 3, furthercomprising: determining one or more antenna locations among theplurality of different antenna location coordinate values to which oneor more beams among the plurality of beams are mapped, wherein the atleast one antenna location used by the estimating corresponds to thedetermined one or more antenna locations.
 5. The method of claim 4,wherein the determining determines multiple candidate antenna locationsto which at least one of the one or more beams is mapped, wherein theestimating estimates multiple candidate position estimates of the UEbased on the multiple candidate antenna locations, and derives theposition estimate for the UE based on the multiple candidate positionestimates.
 6. The method of claim 5, wherein the deriving derives theposition estimate based on the multiple candidate position estimates by:(i) averaging of the multiple candidate position estimates, or (ii)selecting the candidate position estimate that is most congruent withone or more previously estimated position estimates for the UE.
 7. Themethod of claim 1, wherein the at least one antenna location includesthe plurality of different antenna location coordinate values.
 8. Themethod of claim 1, wherein the at least one antenna location includesthe single representative antenna location of the multiple differentantenna location coordinate values.
 9. The method of claim 8, whereinthe single representative antenna location is different than any of themultiple different antenna location coordinate values.
 10. The method ofclaim 8, wherein the single representative antenna location is averagedbetween the multiple different antenna location coordinate values. 11.The method of claim 8, wherein the single representative antennalocation is one of the multiple different antenna location coordinatevalues.
 12. The method of claim 1, wherein the network entitycorresponds to a location server, or wherein the network entitycorresponds to the base station.
 13. The method of claim 12, furthercomprising: transmitting, to the network entity, a request for locationinformation pertaining to the at least one base station, wherein thelocation assistance data is received in response to the request.
 14. Themethod of claim 13, wherein the request further identifies beams beingtransmitted by the base station that are of interest to the UE, andwherein the identified beams of interest correspond to the plurality ofbeams.
 15. A method of operating a network entity, comprising:determining location assistance data that indicates (i) a set of antennalocations associated with at least one base station, the set of antennalocations including at least one antenna location of a base station, theat least one antenna location including a plurality of different antennalocation coordinate values stored in one or more records associated withthe base station, a single antenna location that is representative ofmultiple different antenna location coordinate values stored in at leastone record associated with the base station, or a combination thereof,and (ii) a mapping of each of a plurality of beams to the at least oneantenna location; and transmitting the location assistance data to auser equipment (UE).
 16. The method of claim 15, further comprising:receiving, from the UE, a request for location information pertaining toone or more base stations, wherein the transmitting is performed inresponse to the request.
 17. The method of claim 16, wherein the requestfurther identifies beams being transmitted by the base station that areof interest to the UE, further comprising: configuring the locationassistance data to only include antenna location information for thebase station that is mapped to the identified beams of interest, suchthat the identified beams of interest correspond to the plurality ofbeams.
 18. The method of claim 15, wherein the network entitycorresponds to a location server.
 19. The method of claim 18, whereinthe network entity corresponds to the base station.
 20. The method ofclaim 19, further comprising: transmitting the plurality of beams fromthe at least one antenna location of the base station in accordance withthe mapping.
 21. The method of claim 15, wherein the at least oneantenna location includes the plurality of different antenna locationcoordinate values.
 22. The method of claim 15, wherein the at least oneantenna location includes the single representative antenna location ofthe multiple different antenna location coordinate values.
 23. Themethod of claim 22, wherein the single representative antenna locationis different than any of the multiple different antenna locationcoordinate values.
 24. The method of claim 23, wherein the singlerepresentative antenna location is averaged between the multipledifferent antenna location coordinate values.
 25. The method of claim22, wherein the single representative antenna location is one of themultiple different antenna location coordinate values.
 26. A userequipment (UE), comprising: a memory; at least one transceiver; and atleast one processor coupled to the memory and the at least onetransceiver configured to: receive, from a network entity, locationassistance data that indicates (i) a set of antenna locations associatedwith at least one base station, the set of antenna locations includingat least one antenna location of a base station, the at least oneantenna location including a plurality of different antenna locationcoordinate values stored in one or more records associated with the basestation, a single antenna location that is representative of multipledifferent antenna location coordinate values stored in at least onerecord associated with the base station, or a combination thereof, and(ii) a mapping of each of a plurality of beams to the at least oneantenna location; and receive, from the base station, the plurality ofbeams in accordance with the mapping.
 27. The UE of claim 26, whereinthe at least one processor is further configured to: estimate a positionof the UE based at least in part upon (i) the one or more measurementsperformed by the UE on the one or more of the plurality of beams and(ii) the at least one antenna location to which the one or more beamsare mapped.
 28. The UE of claim 26, wherein the at least one antennalocation includes the plurality of different antenna location coordinatevalues.
 29. A network entity, comprising: a memory; at least onecommunication interface; and at least one processor coupled to thememory and the at least one communication interface and configured to:determine location assistance data that indicates (i) a set of antennalocations associated with at least one base station, the set of antennalocations including at least one antenna location of a base station, theat least one antenna location including a plurality of different antennalocation coordinate values stored in one or more records associated withthe base station, a single antenna location that is representative ofmultiple different antenna location coordinate values stored in at leastone record associated with the base station, or a combination thereof,and (ii) a mapping of each of a plurality of beams to the at least oneantenna location; and transmit the location assistance data to a userequipment (UE).
 30. The network entity of claim 29, wherein the at leastone antenna location includes the plurality of different antennalocation coordinate values.